In recent years, with the arrival of digital home, various digital home appliances used in people's family life communicate with each other via home network, so that information sharing and device control can be implemented on a home network platform. Television is an important digital home appliance in family life. Digitization and intellectualization requirements for the television are higher and higher. In the current field of digital television, there are different kinds of external digital devices which could be applied to the television, such as a high definition network set-top box, a smart TV box, a TV card and so on. It is a popular to connect these external digital devices to the digital television by a routing device, in which case a combined television is presented by researchers.